1. Field
The disclosure relates to a method and system for the adjustment of temperature in a hot roller.
2. Background
In certain laser printers, a laser draws the printable image on a special light-sensitive optical photo conducting drum. The light sensitive drum collects powdered ink, also referred to as toner, using an electrostatic charge and allows the toner to be transferred to a page of paper. The dry, powdery toner has to be melted to become a permanent image on the page. To melt the toner, the page is rolled between a hot fuser roller, also referred to as a hot roller, and at least one unheated pressure roller, also referred to as a backup roller. One or more infrared lamps, such as halogen lamps, included inside the hot roller may heat the hot roller up to a temperature high enough to melt and fuse the toner to the page.
For example, the IBM* Infoprint* 4100 comprises a continuous forms printing system that has two electrophotographic printers, called engines, which allow printing on both sides of the paper. In the IBM Infoprint 4100, the toner is electrostatically deposited onto a photoconductive drum and then transmitted electrostatically to the paper. The paper then travels between two rollers, a hot roller and a backup roller, which apply heat and pressure respectively to fuse the toner to the paper. In the IBM Infoprint 4100, the page also flows over a preheated platen, where the preheated platen is used to preheat the paper before the paper reaches the hot roller, in order to aid in achieving the necessary paper temperature for the toner to fuse correctly. The hot roller may be an aluminum tube coated with a layer of silicon rubber. There are four internal tungsten quartz filament lamps of different length and position inside the hot roller, which collectively heat the hot roller. The backup roller is also an aluminum tube, but without heating elements. The backup roller applies pressure to fuse the toner to the paper. Due to the soft nature of the silicon rubber coating, when the hot roller and backup roller are in contact, they may form a nip area of approximately 10 mm. This allows for sufficient area and time to fuse the toner to the paper. To prevent the toner from adhering to the hot roller, the hot roller is coated with silicon oil. This is accomplished from a cloth material saturated in the oil. When the printer is running, the cloth is in contact with the hot roller. A smaller positioning roller may be used to optimize the paper direction before the paper proceeds between the hot roller and backup roller. * IBM and Infoprint are trademarks or registered trademarks of International Business Machines Corporation